how to change the maximum number of connection to Oracle database?

Solution 1:

are you also changing PROCESSES parameter afterwards? sessions is a derived parameter.

Try changing sessions last?

Solution 2:

1. Change:

   echo "alter system set processes=1000 scope=spfile;" | sqlplus system/password@localhost:1521/orcl

   echo "alter system set sessions=1000 scope=spfile;" | sqlplus system/password@localhost:1521/orcl

2. Restart DB

3. Check:

   echo "SELECT value FROM v\$parameter WHERE name = 'processes';" | sqlplus system/password@localhost:1521/orcl

   echo "SELECT value FROM v\$parameter WHERE name = 'sessions';" | sqlplus system/password@localhost:1521/orcl